Night vision devices are widely used in the military to provide soldiers, aviators and sailors with the ability to view objects at night or during other low light conditions. As a result, many night vision devices are currently being manufactured according to exacting military specifications and designs. Similarly, many such night vision devices are being manufactured for specific military applications such as part of the sights of various weapons or as part of goggle assemblies that attach to an aviator's or soldier's helmet. As a consequence, many of the night vision devices currently being manufactured are neither affordable nor easily adapted to non-military uses by the general public.
Night vision devices typically include an image intensifier tube that converts infrared energy into visible light. Such night vision devices typically require sophisticated power supplies and circuitry to control the operation of the image intensifier tube and sophisticated optical arrangements that direct the infrared energy into the image intensifier tube and visible light away from the image intensifier tube. In military applications, the various military personnel are trained in how to use and adjust the night vision devices they are issued. However, a night vision device designed for use by the general public would have to provide simple adjustments that can be readily operated by a variety of different users in a dark environment. Furthermore, a night vision device designed for use by the general public would also require various adjustable optical characteristics that would be easy to operate and adjust. Such a consumer oriented night vision device would have wide ranging application in regard to nighttime marine piloting, nighttime security, surveillance, hunting, fishing, backpacking, navigation, underwater vision, search and rescue and law enforcement.
ITT Corporation, the assignee herein, manufactures many night vision devices for various applications. Night vision devices for military applications are exemplified by U.S. Pat. No. 5,084,780 to Phillips entitled TELESCOPIC SIGHT FOR DAY/NIGHT VIEWING and U.S. Pat. No. 5,029,963 to Naselli entitled REPLACEMENT DEVICE FOR A DRIVER'S VIEWER. ITT Corporation, also has designed handheld night vision binoculars devices. Such a binocular device is exemplified in U.S. patent application Ser. No. 07/954,006, entitled CONSUMER NIGHT VISION VIEWING APPARATUS and filed on Sep. 30, 1992. In this application, a night vision binocular device is disclosed having simplified adjustment controls, interpupillary adjustments and diopter cell focus adjustments. Related optical components that can be utilized in the construction of night vision binocular devices are shown in U.S. patent application Ser. No. 08/039,755, now U.S. Pat. No. 5,347,397 entitled DIOPTER CELL ASSEMBLY FOR A BINOCULAR VIEWING SYSTEM, and U.S. Pat. No. 5,117,553, entitled COLLIMATOR FOR A BINOCULAR VIEWING SYSTEM, both of which are assigned to the assignee herein. These references show a diopter cell design and a collimator lens assembly for night vision binoculars, respectively. The assignee holds many other patents and applications related to image intensifier tubes and related devices which are of interest in regard to the present subject matter.
As has been previously mentioned, an important application for publicly available night vision devices will be for use on recreational boats. Boats often run at night utilizing only their running lights for illumination. The use of night vision devices by the pilots of boats will greatly increase visibility, resulting in less nighttime collisions and similar accidents. The night vision binoculars will enable boaters to identify objects detected on radar, see land marks, read channel markers, detect navigational hazards, identify approaching vessels and much more. The environment of a recreational boat is less than ideal for a sophisticated electro-optical device such as a handheld night vision instrument. To survive in such an environment, the night vision instrument must be capable of withstanding large temperature changes, impacts, and must be hermetically sealed to withstand the high humidity environment and the possibility of being dropped into the water. Furthermore, since most recreational boats are small, inexpensive craft, the night vision device must provide the same performance as military specificating night vision devices but at a greatly reduced cost so as to be affordable to the average boater.
It is therefore the object of the present invention to provide a night vision device that is easy to hold, easy to operate, water proof and provides the same performance as military night vision devices at a greatly reduced cost.
It is a further object of the present invention to provide component parts for the above-mentioned night vision device that are easy to manufacture and assembly, thereby further reducing the cost of manufacturing the night vision device.